Currently, the increase in the functionality of various electronic devices is driving the demand for smaller and smaller devices that are easier and more convenient for users to carry and use. This causes many electrical/electronic components within the device to be located closer together. This increases the possibility that various electronic components in the device will suffer from electromagnetic interference (EMI) or radio frequency interference (RFI) either from RF components such as the antenna, microphone components, RF power amplifiers, etc and subsystems in the device and/or from external sources. The high speed electrical transmission in these devices can produce electromagnetic emissions, which may leak from the connection between the plug connector and its mating connector. These emissions can cause problems in high speed signal transmissions in that they can negatively influence wireless communication between two devices.
When electrical connectors are made smaller, the conductive contacts or pins of electrical connectors are brought closer to each other thereby increasing the electromagnetic coupling between the electrical connectors. An increase in electromagnetic coupling between differential signal pairs may generate unwanted noise or crosstalk that negatively affects the performance of the electrical connector and increase EMI/RFI leakage. One particular concern regarding electrical connector is reducing electromagnetic interference (EMI) or radio frequency interference (RFI) so as to meet the relevant EMI regulations or RFI regulations. There is a need not only to minimize the EMI or RFI of electrical connectors but also to contain the EMI or RFI of the host system in which the electrical connector assembly is mounted, regardless of whether a plug connector is inserted into a receptacle connector.
In conventional designs, EMI shielding is achieved using the metallic shell. The metallic shell is typically stamped to form spring fingers. These spring fingers are then bent to form finger contacts. These finger contacts form an electrical connection with a shield on the connector insert and hold the connector insert when it is placed in a connector receptacle. EMI leakage still occurs in such structure. However, due to the increasing of the speed rate of signals being transmitted through the electrical connector assemblies when a plug connector is inserted into a receptacle connector, the EMI shielding or RFI shielding provided by conventional shell is proving to be inadequate.